Abbott-Smith Manual Greek Lexicon
κῆτος (G2785)
1 κῆτος , -εος ( -ους ), τό , [in LXX: Jh 2:1 , 11 ( דָּג ), Ge 1:21 ( תַּנִּין ), etc.;] a huge fish , sea-monster : Mt 12:40 (LXX) .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain